1. Field of the Invention
The present invention relates generally to a metal-air fuel cell, and in particular to an anode structure of the metal-air fuel cell battery.
2. Description of the Prior Art
Batteries have been developed and widely used in a variety of fields. A variety of batteries are currently available, including lead-acid battery, zinc-manganese battery, nickel-cadmium battery, nickel-hydride battery, lithium ion battery, and metal-air fuel cell, such as zinc-air fuel cell battery. In recent year, emphasis has been placed on the metal-air fuel cell because of its high energy density and potential long shelf life. The overall reaction is oxidation of metal, such as zinc, and the reaction release electrons.
FIG. 1 of the attached drawings shows a conventional zinc-air fuel cell battery in which the anode comprises a zinc plate as the fuel of the battery. As shown, the battery comprises a zinc plate 1 as the anode arranged between cathode plates 2. Air 3 containing oxygen penetrates through the cathode plates 2 to enter the battery. Oxygen of the air reacts with the cathode plate 2 and becomes oxygen ions entering the electrolyte of the battery. The zinc plate 1 is positioned in the electrolyte and reacts with the electrolyte to release energy. The anode 1 and cathode 2 have terminals 10, 20 for external connection.
The surface area of the zinc plate of the zinc-air battery is a critical factor that affects the electrical performance of the battery. The larger the surface area of the zinc plate is, the larger the energy can be released at a predetermined time interval. This is still one of the major issues of the metal-air fuel cell to be addressed.
In addition, the conventional zinc-air fuel cell battery has a low energy density which causes problems in supply of large power. Thus, improving the zinc-air fuel cell battery in order to supply large power is another major issue to be addressed.
Thus, a primary object of the present invention is to provide a metal-air fuel cell comprising an anode structure for providing an increased contact surface area between the zinc fuel plate and air for enhancing reaction speed and efficiency.
Another object of the present invention is to provide a metal-air fuel cell comprising an anode plate having a plurality of apertures to enhance the performance of the battery.
A further object of the present invention is to provide a metal-air fuel cell comprising an anode plate having a plurality of fins extending therefrom to enhance the performance of the battery.
To achieve the above objects, in accordance with the present invention, there is provided a metal-air fuel cell comprising an anode and a cathode with an electrolyte between the anode and the cathode. The anode includes a plate-like body made of a composite plate including a reaction layer, a reaction-enhancing layer and a collector layer. A plurality of fins are formed on and extending from a major surface of the plate-like body. A plurality of openings are selectively defined in the plate-like body in correspondence to the fins. The fins can be arranged in an array with fins in adjacent rows aligned with each other or offset with respect to each other. If desired, the plate can be made wavy.